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1.
Angiology ; 50(4): 349-53, 1999 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10225474

RESUMO

Central venous line malpositioning in the left mediastinum is a rare event. A case of left superior intercostal vein central venous line placement is reported. Chest radiographs, especially lateral views and contrast studies, are useful for position evaluation. Catheter removal is prudent although the purpose of the catheter and the symptomatology can dictate further management of the malpositioned catheter.


Assuntos
Cateterismo Venoso Central/efeitos adversos , Mediastino , Idoso , Veia Ázigos/diagnóstico por imagem , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/terapia , Meios de Contraste , Feminino , Humanos , Veias Jugulares , Mediastino/diagnóstico por imagem , Radiografia , Veia Cava Superior/diagnóstico por imagem
2.
J Surg Oncol ; 70(1): 54-9, 1999 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9989422

RESUMO

BACKGROUND AND OBJECTIVES: Small cell carcinoma of the gallbladder is rare with only 36 cases reported in the literature. Early reports demonstrated an extremely poor prognosis for this histologic type. Five new cases are reported and the previous experience in the literature is reviewed to further clarify the clinical behavior of this malignancy. METHODS: A retrospective analysis is performed on 5 new cases. An extensive review of the literature is also performed. RESULTS: Twenty-eight pure small cell carcinomas and 8 combined small cell carcinomas with adenocarcinoma are reported in the literature. Conclusions from the literature review reveal that small cell carcinoma of the gallbladder affects an elderly patient population (median age 65 years), has a female preponderance (76%), is associated with cholelithiasis (72%), metastasizes to nodes (88%), liver (88%), lung (23%), and peritoneum (19%), and has a median survival of 4 months. Pure tumors had median survivals of 9 months and combined tumors had median survivals of 4.5 months. The 5 patients in the literature treated with surgery and chemotherapy had improved median survival of 13 months. The 5 newly reported cases had similar epidemiological characteristics to the literature data, however, these cases were managed aggressively with surgery and chemotherapy, demonstrating a median survival of 31 months. CONCLUSIONS: Although small cell carcinoma of the gallbladder is a distinct histologic and clinical entity, it has many clinical characteristics similar to adenocarcinoma of the gallbladder including comparable natural history and tendency for locoregional spread. Aggressive multimodality therapy, especially the combination of surgery and chemotherapy, may improve survival.


Assuntos
Carcinoma de Células Pequenas , Neoplasias da Vesícula Biliar , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma de Células Pequenas/mortalidade , Carcinoma de Células Pequenas/patologia , Carcinoma de Células Pequenas/cirurgia , Colecistectomia Laparoscópica , Terapia Combinada , Feminino , Neoplasias da Vesícula Biliar/mortalidade , Neoplasias da Vesícula Biliar/patologia , Neoplasias da Vesícula Biliar/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Fumar , Taxa de Sobrevida
3.
J Cell Physiol ; 178(3): 296-303, 1999 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9989775

RESUMO

Transforming growth factorbeta1 (TGFbeta1) elicits a multitude of cellular responses from the epithelial-derived human colon cancer Moser cells. TGFbeta1 induces the expression of laminin and fibronectin, and previous studies show that the induction of fibronectin is functionally associated with the regulation of carcinoembryonic antigen (CEA) expression by TGFbeta1 (Huang and Chakrabarty, 1994, J Biol Chem 269:28764-28768). In this study we constructed antisense laminin chain-specific expression vectors and determined their efficacy in blocking the expression and the induction of the large multichain laminin molecule by TGFbeta1. We also determined the functional role of laminin in several TGFbeta1-mediated responses: growth inhibition, downmodulation of anchorage-independent growth, and cellular invasion. Expression of either antisense laminin chain A, B1, or B2 RNA resulted in a downmodulation of endogenous laminin mRNA expression and blocked the induction of laminin protein by TGFbeta1 without affecting the induction of other adhesion molecules such as fibronectin or CEA. It is concluded that antisense RNA directed to only one of the laminin chains was sufficient to disrupt the induction of the complex laminin molecule in quite a specific manner. Expression of antisense laminin RNA downregulated cellular adhesion to extracellular matrix (ECM) laminin and blocked the ability of TGFbeta1 to upmodulate adhesion to ECM laminin. Expression of antisense laminin RNA, however, did not alter the downregulating effect of TGFbeta1 on cellular proliferation, anchorage-independent growth, or cellular invasion, suggesting that the induction of laminin did not play a significant functional role in these TGFbeta1-mediated cellular responses. It is likely that other adhesion pathways may be involved in mediating the action of TGFbeta1 in this cell line.


Assuntos
Laminina/genética , Transcrição Gênica , Fator de Crescimento Transformador beta/farmacologia , Antígeno Carcinoembrionário/biossíntese , Antígeno Carcinoembrionário/genética , Adesão Celular , Divisão Celular , Neoplasias do Colo , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/fisiologia , Matriz Extracelular/fisiologia , Fibronectinas/biossíntese , Fibronectinas/genética , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Vetores Genéticos , Humanos , Laminina/biossíntese , Invasividade Neoplásica , RNA Antissenso , Transfecção , Células Tumorais Cultivadas
4.
Ann Thorac Surg ; 66(4): 1128-33, 1998 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9800793

RESUMO

BACKGROUND: Conventional therapy for pleural mesothelioma has met with disappointing results. METHODS: From 1991 to 1996, 40 patients with malignant pleural mesothelioma were treated with surgical resection followed by immediate intracavitary photodynamic therapy. RESULTS: The series included 9 women and 31 men with a mean age of 60 years. Morbidity and treatment-related mortality rates for the entire series, pleurectomy, and extrapleural pneumonectomy were 45% and 7.5%, 39% and 3.6%, and 71% and 28.6%, respectively. Median survival and the estimated 2-year survival rate for the entire series, stages I and II patients (n = 13), and stages III and IV patients (n = 24) were 15 months and 23%, 36 months and 61%, and 10 months and 0%, respectively. Multivariate analysis identified stage, length of hospital stay, photodynamic therapy dose, and nodal status as independent prognostic indicators for survival. CONCLUSIONS: Surgical intervention and photodynamic therapy offer good survival results in patients with stage I or II pleural mesothelioma. For patients in stage III or IV, better treatment modalities need to be developed. Improvements in early detection and preoperative staging are necessary for proper patient selection for treatment.


Assuntos
Fotorradiação com Hematoporfirina , Mesotelioma/tratamento farmacológico , Mesotelioma/cirurgia , Neoplasias Pleurais/tratamento farmacológico , Neoplasias Pleurais/cirurgia , Pneumonectomia , Antineoplásicos/uso terapêutico , Terapia Combinada , Éter de Diematoporfirina/uso terapêutico , Feminino , Seguimentos , Humanos , Masculino , Mesotelioma/mortalidade , Pessoa de Meia-Idade , Neoplasias Pleurais/mortalidade , Modelos de Riscos Proporcionais , Análise de Sobrevida , Taxa de Sobrevida
5.
Lab Invest ; 78(4): 413-21, 1998 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9564886

RESUMO

Transforming growth factor beta1 (TGFbeta1) inhibits cellular proliferation and induces the expression of the matrix adhesion molecules fibronectin (FN) and laminin (LM) in a concurrent manner, followed by the induction of the intercellular adhesion molecule carcinoembryonic antigen (CEA) (collectively designated as adhesion responses) in TGFbeta1-responsive human colon carcinoma cells. Exactly how TGFbeta1 controls cellular adhesion and proliferation is poorly understood. In the present report, we showed that down-regulating protein kinase Calpha (PKCalpha) expression blocked the induction of these adhesion responses by TGFbeta1, showing that PKCalpha is a postreceptor focal point controlling the induction of these molecules. Down-regulating PKCalpha expression, however, had minimal effect on the antiproliferative response to TGFbeta1 or the induction of p21/WAF1, a marker associated with the antiproliferative effect of TGFbeta1, demonstrating that the adhesion signal pathway is distinct from that of antiproliferation. Blockade of FN induction blocked the induction of CEA but not the induction of LM. Blockade of LM induction, on the other hand, had no effect on the induction of FN and CEA. These results established the existence of two distinct and parallel postPKCalpha adhesion signal pathways, one leading to the induction of LM and the other leading to the induction of FN and CEA.


Assuntos
Adesão Celular/efeitos dos fármacos , Isoenzimas/fisiologia , Proteína Quinase C/fisiologia , Fator de Crescimento Transformador beta/farmacologia , Antígeno Carcinoembrionário/biossíntese , Divisão Celular/efeitos dos fármacos , Neoplasias do Colo , Fibronectinas/biossíntese , Humanos , Laminina/biossíntese , Células Tumorais Cultivadas
6.
Surg Oncol ; 7(1-2): 5-12, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-10421502

RESUMO

Malignant pleural mesothelioma is a rare tumor that has been difficult to study. Because of disappointing treatment results, malignant pleural mesothelioma has remained an area of active research and development. A clinicopathologic review is performed in light of several problematic issues involving diagnosis, staging, natural history, and treatment. Multimodality treatment with surgery followed by adjuvant local and systemic therapy remains the most optimal therapy. Many controversial issues still exist in the treatment of malignant pleural mesothelioma. In the ensuing years newer staging systems, better preoperative staging, newer experimental therapies, and the localization of patients at expert centers will undoubtedly have an impact on disease management.


Assuntos
Mesotelioma/etiologia , Neoplasias Pleurais/etiologia , Adulto , Idoso , Ensaios Clínicos como Assunto , Feminino , Humanos , Masculino , Mesotelioma/epidemiologia , Mesotelioma/terapia , Pessoa de Meia-Idade , Invasividade Neoplásica , Estadiamento de Neoplasias , Neoplasias Pleurais/epidemiologia , Neoplasias Pleurais/terapia , Taxa de Sobrevida , Tomografia Computadorizada por Raios X
7.
J Natl Cancer Inst ; 89(21): 1602-8, 1997 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-9362158

RESUMO

BACKGROUND: When given during pregnancy, the drug 3'-azido-2',3'-dideoxythymidine (AZT) substantially reduces maternal-fetal transmission of human immunodeficiency virus type 1 (HIV-1). However, AZT has been shown to be carcinogenic in adult mice after lifetime oral administration. In this study, we assessed the transplacental tumorigenic and genotoxic effects of AZT in the offspring of CD-1 mice and Erythrocebus patas monkeys given AZT orally during pregnancy. METHODS: Pregnant mice were given daily doses of either 12.5 or 25.0 mg AZT on days 12 through 18 of gestation (last 37% of gestation period). Pregnant monkeys were given a daily dose of 10.0 mg AZT 5 days a week for the last 9.5-10 weeks of gestation (final 41%-43% of gestation period). AZT incorporation into nuclear and mitochondrial DNA and the length of chromosomal end (telomere) DNA were examined in multiple tissues of newborn mice and fetal monkeys. Additional mice were followed from birth and received no further treatment until subjected to necropsy and complete pathologic examination at 1 year of age. An anti-AZT radioimmunoassay was used to monitor AZT incorporation into DNA. RESULTS: At 1 year of age, the offspring of AZT-treated mice exhibited statistically significant, dose-dependent increases in tumor incidence and tumor multiplicity in the lungs, liver, and female reproductive organs. AZT incorporation into nuclear and mitochondrial DNA was detected in multiple organs of transplacentally exposed mice and monkeys. Shorter chromosomal telomeres were detected in liver and brain tissues from most AZT-exposed newborn mice but not in tissues from fetal monkeys. CONCLUSIONS: AZT is genotoxic in fetal mice and monkeys and is a moderately strong transplacental carcinogen in mice examined at 1 year of age. Careful long-term follow-up of AZT-exposed children would seem to be appropriate.


Assuntos
Carcinógenos/efeitos adversos , DNA de Neoplasias/efeitos dos fármacos , Zidovudina/efeitos adversos , Animais , Animais Recém-Nascidos , DNA Mitocondrial/efeitos dos fármacos , Relação Dose-Resposta a Droga , Erythrocebus patas , Feminino , Feto/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos , Placenta , Gravidez , Radioimunoensaio , Telômero/efeitos dos fármacos
8.
J Trauma ; 43(2): 368-9, 1997 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9291391

RESUMO

A case of subclavian artery obstruction by tube thoracostomy for penetrating trauma is presented. The obstruction was not physiologically significant; however, it did impede the assessment of the subclavian artery for potential injury using emergency center arteriography. The difficulty was easily corrected with repositioning of the chest tube. This previously undescribed complication of tube thoracostomy is presented with its clinical implications.


Assuntos
Tubos Torácicos/efeitos adversos , Hemotórax/terapia , Pneumotórax/terapia , Artéria Subclávia , Traumatismos Torácicos/complicações , Toracostomia/efeitos adversos , Ferimentos Perfurantes/complicações , Adulto , Constrição Patológica/diagnóstico por imagem , Constrição Patológica/etiologia , Hemotórax/etiologia , Humanos , Masculino , Pneumotórax/etiologia , Radiografia
9.
Reprod Toxicol ; 11(1): 95-100, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9138639

RESUMO

A previous attempt to model transplacental cisplatin exposure and genotoxicity employed several pregnant Erythrocebus patas monkeys; most of the animals were exposed near the end of gestation and cisplatin-DNA adduct analyses included only genomic DNA. Here, both genomic and mitochondrial DNA adduct formation have been determined in fetuses from two pregnant monkeys exposed at the end of the second trimester of gestation. Multiple fetal tissues were obtained after doses of 0.315 mg cisplatin/kg body weight (5.3 mg/m2 total) on days 101 and 106 of gestation. Cesarean sections were performed 24 h after exposure and 27 d after exposure. Cisplatin genomic (g)-DNA adducts were observed in fetal adrenal, brain, heart, kidney, liver, skin, spleen, and thymus. When placentas from the two animals were divided into four concentric regions at increasing distances from the umbilical cord, and g-DNA was assayed, cisplatin DNA adduct levels were similar in all four regions. Mitochondrial (mt)-DNA adducts were higher than g-DNA adducts in maternal liver and fetal liver, brain and kidney, suggesting that the mitochondria may constitute a particular target for cisplatin genotoxicity. The study demonstrates significant fetal genotoxicity in g-DNA and mt-DNA of patas monkeys exposed to cisplatin in utero, suggesting that similarly exposed human fetuses may also sustain drug-induced DNA damage.


Assuntos
Cisplatino/administração & dosagem , Cisplatino/toxicidade , Dano ao DNA , DNA Mitocondrial/efeitos dos fármacos , Desenvolvimento Embrionário e Fetal/efeitos dos fármacos , Troca Materno-Fetal/efeitos dos fármacos , Placenta/metabolismo , Animais , Adutos de DNA/efeitos dos fármacos , Desenvolvimento Embrionário e Fetal/genética , Erythrocebus patas , Feminino , Especificidade de Órgãos/efeitos dos fármacos , Especificidade de Órgãos/genética , Placenta/efeitos dos fármacos , Gravidez , Efeitos Tardios da Exposição Pré-Natal
10.
J Med Virol ; 50(4): 289-92, 1996 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8950684

RESUMO

Two chimpanzees were inoculated subcutaneously with the wild-type Oka strain of varicellazoster virus (VZV). Viral DNA was detected in peripheral blood mononuclear cells of both animals using the polymerase chain reaction (PCR) shortly after inoculation. Ten days after inoculation both animals developed an erythematous, papular rash near the site of inoculation that extended into the adjacent dermatome. Viral DNA was found by PCR in a skin biopsy from one of the animals at the time of the rash. While only two animals were studied, the development of a mild form of varicella in chimpanzees indicates that these animals might be useful for molecular studies of viral genes involved in virulence or attenuation of VZV.


Assuntos
Varicela , Modelos Animais de Doenças , Pan troglodytes , Animais , Varicela/virologia , DNA Viral/análise , DNA Viral/sangue , Herpesvirus Humano 3/genética , Herpesvirus Humano 3/isolamento & purificação , Leucócitos Mononucleares/virologia , Pan troglodytes/virologia , Reação em Cadeia da Polimerase , Pele/virologia
11.
Int J Cancer ; 66(1): 130-4, 1996 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-8608956

RESUMO

N-nitrosodimethylamine (NDMA) is a human cancer initiator suspect. Ethanol, a cancer risk factor, may synergize with nitrosamines by suppressing hepatic clearance, to increase internal exposure. A limitation to these hypotheses is lack of activation of NDMA by many rodent tissues. However, systemtic primate studies are lacking. Patas monkeys were utilized to investigate NDMA activation by primate tissues in vivo, generating the promutagenic DNA lesion 0(6)-methylguanine (0(6)-meG). Adult monkeys received 0. 1 mg/kg NDMA by gavage, in some cases preceded by ethanol. Four hours after NDMA only, 0(6)-meG was detected in DNA from all tissues. Levels were highest in gastric mucosa and liver and were only about 50% lower in DNA from white blood cells, esophagus, ovary, pancreas, urinary bladder and uterus. With ethanol co-exposure, amounts of 0(6)-meG increased at least 2-fold in all tissues except liver. The largest effect was in esophagus (17-fold increase), followed by ovary, large intestine, urinary bladder, spleen and cerebellum (9- to 13-fold increases), and uterus, cerebrum and brain stem (7- to 8-fold increases). Alkylguanine alkyltransferase activities varied over a 30-fold range and were highest in liver and stomach. Thus primate tissues, especially those of the gastrointestinal and urogenital organs, are sensitive targets for DNA adduct damage due to NDMA, and ethanol co-exposure leads to striking increases in adducts. Our data support epidemiology implicating nitrosamines in causation of cancers of stomach and other organs, and alcohol as enhancing internal exposure to nitrosamines.


Assuntos
Carcinógenos , Adutos de DNA/metabolismo , Dano ao DNA , Compostos Nitrosos , Alquilação , Animais , Sistema Digestório/metabolismo , Erythrocebus patas , Etanol/administração & dosagem , Feminino , Masculino , Metiltransferases/metabolismo , O(6)-Metilguanina-DNA Metiltransferase , Sistema Urogenital/metabolismo
12.
Int J Cancer ; 62(6): 661-7, 1995 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-7558411

RESUMO

Human colon cancer cell lines express epidermal growth factor (EGF) mRNA, secrete EGF and may respond to it via the cell-surface EGF receptor (EGFR). Expression of these molecules in human colon and colon tumor, however, is not clear. Reverse transcription-polymerase chain reaction (RT-PCR) analyses of RNA prepared from paired normal human colon and colon tumor samples from 12 individuals followed by Southern blotting analyses of the RT-PCR products revealed a major fragment of 527 bp and a minor fragment of 404 bp that hybridized to a human EGF cDNA probe under stringent conditions. Identical results were obtained from 8 human colon cancer cell lines. Cloning and sequencing of PCR products confirmed that both fragments were from the human EGF gene; the 527-bp fragment corresponded exactly to nucleotides 2,891 to 3,417 of the human EGF mRNA reported by others. A deletion of 123 nucleotides (nucleotides 3,172 to 3,294) was found in the 404-bp fragment. Immunohistochemical studies using cyostat sections of human colon specimens showed that EGF was expressed in the human colon and that expression was restricted to the epithelial colonic crypt cells and epithelium-derived cancer cells. Since EGF and EGF-related molecules are potent mitogens that mediated their effect through the EGFR, we also determined the efficacy of anti-sense EGFR RNA in circumventing the EGFR-related pathway of proliferation. Expression of anti-sense EGFR RNA, by transfection with an inducible anti-sense EGFR expression vector, down-regulated cell-surface EGFR expression and proliferation of these cells and their ability to grow in soft agar. Anti-sense EGFR RNA was found to be an anti-proliferative agent in both relatively non-aggressive and highly aggressive human colon cancer cells.


Assuntos
Adenocarcinoma/metabolismo , Colo/metabolismo , Neoplasias do Colo/metabolismo , Fator de Crescimento Epidérmico/biossíntese , Receptores ErbB/fisiologia , RNA Antissenso/fisiologia , Adenocarcinoma/patologia , Sequência de Bases , Southern Blotting , Divisão Celular/efeitos dos fármacos , Divisão Celular/fisiologia , Clonagem Molecular , Neoplasias do Colo/química , Neoplasias do Colo/patologia , Regulação para Baixo/fisiologia , Fator de Crescimento Epidérmico/genética , Epitélio/metabolismo , Receptores ErbB/biossíntese , Receptores ErbB/genética , Humanos , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , RNA Antissenso/genética , RNA Mensageiro/análise , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Sefarose , Transcrição Gênica , Transfecção , Células Tumorais Cultivadas
13.
Cancer Epidemiol Biomarkers Prev ; 4(2): 127-31, 1995 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-7742720

RESUMO

Transforming growth factor alpha (TGF alpha), a polypeptide growth-stimulating factor, has been implicated to play a role in the progression of gastrointestinal (GI) cancer. It has been suggested that TGF alpha expression in tumors or TGF alpha in the biological fluids of cancer patients may have tumor marker value. The serum levels of TGF alpha in GI cancer patients have not been reported. In this study, the serum TGF alpha levels of 100 GI cancer patients, as well as 74 healthy individuals, were determined by a TGF alpha-specific RIA kit. All of the cancer patient sera and 67% of the normal sera had detectable levels of TGF alpha. The TGF alpha concentrations in GI cancer patients ranged from 119 to 760 pg/ml, with a mean value of 269 +/- 102 pg/ml. Fifty normal individuals had detectable levels of TGF alpha, and their levels ranged from 120 to 207 pg/ml, with a mean value of 147 +/- 18 pg/ml. Differences in serum TGF alpha concentration between cancer patients and healthy individuals were found to be statistically significant, as evaluated by Mann-Whitney and Student's t tests. Serum TGF alpha levels were found to be significantly elevated in all disease stages of gastric, pancreas, colon, and rectal cancers, and only in the late stages of esophageal cancer. Serum carcinoembryonic antigen levels were significantly elevated only in the late stages of these diseases. The potential of serum TGF alpha as a tumor marker for GI malignancy, therefore, warrants further investigation.


Assuntos
Neoplasias Gastrointestinais/sangue , Fator de Crescimento Transformador alfa/sangue , Adulto , Idoso , Biomarcadores Tumorais/sangue , Antígeno Carcinoembrionário/sangue , Estudos de Casos e Controles , Neoplasias do Colo/sangue , Neoplasias Esofágicas/sangue , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Neoplasias Pancreáticas/sangue , Neoplasias Retais/sangue , Sensibilidade e Especificidade , Neoplasias Gástricas/sangue
14.
J Med Virol ; 43(2): 135-42, 1994 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-8083660

RESUMO

The infectivity titer of a standard stock of the SAR-55 strain of hepatitis E virus (HEV) was determined in cynomolgus macaques (Macaca fascicularis) and the effect of dose on the course of the infection was examined by weekly monitoring of alanine aminotransferase (ALT) and anti-HEV levels. Antibody to HEV (anti-HEV) was measured with ELISAs based on ORF-2 recombinant antigens consisting of either a 55 kDa region expressed in insect cells or shorter regions expressed as fusion proteins in bacteria. The ELISA based on the 55 kDa antigen was generally more sensitive. The infectivity titer of SAR-55 was 10(6) cynomolgus 50% infectious doses per gram of feces. The infectivity titer corresponded to the HEV genome titer of the inoculum as determined by reverse transcriptase-polymerase chain reaction (RT-PCR). Anti-HEV IgM was detected in only a portion of the animals that had an anti-HEV IgG response. Biochemical evidence of hepatitis was most prominent in animals that were inoculated with the higher concentrations of virus and the incubation period to seroconversion was prolonged in animals that received the lower doses.


Assuntos
Vírus da Hepatite E/patogenicidade , Hepatite E/microbiologia , Alanina Transaminase/sangue , Animais , Anticorpos Anti-Hepatite/sangue , Antígenos E da Hepatite B , Hepatite E/sangue , Hepatite E/imunologia , Vírus da Hepatite E/isolamento & purificação , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Macaca fascicularis
15.
Cancer Lett ; 79(2): 157-60, 1994 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-8019973

RESUMO

Previous studies suggest that transforming growth factor-alpha (TGF alpha) may have the potential of a tumor marker. Since the levels of serum TGF alpha in cancer patients and healthy individuals have not been reported, we determined the serum TGF alpha levels of 83 breast cancer patients and 74 healthy individuals by using a TGF alpha radioimmunoassay kit. All of the cancer patients' sera were positive for TGF alpha; their TGF alpha concentrations ranged from 210 to 740 pg/ml, with a mean of 353 +/- 98 pg/ml. Sixty-seven percent (50 cases) of normal sera were positive for TGF alpha; the levels ranged from 120 to 207 pg/ml, with a mean of 144 +/- 17 pg/ml. The difference in serum TGF alpha levels between cancer patients of different disease stages and healthy individuals was found to be statistically significant by Student t-test and the Mann-Whitney test. No correlation was found between serum carcinoembryonic antigen and TGF alpha levels. The potential of serum immunoreactive TGF alpha as a marker for breast cancer warrants further investigation.


Assuntos
Neoplasias da Mama/sangue , Fator de Crescimento Transformador alfa/sangue , Adulto , Idoso , Neoplasias da Mama/patologia , Antígeno Carcinoembrionário/sangue , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Valores de Referência
16.
Reprod Toxicol ; 8(3): 207-16, 1994.
Artigo em Inglês | MEDLINE | ID: mdl-8075509

RESUMO

Platinum-DNA adducts in placenta and blood from a woman exposed to 200 mg/m2 of cis-diamminedichloroplatinum(II) (cisplatin) and 300 mg/m2 diamminecyclobutanedicarboxylatoplatinum(II) (carboplatin) for ovarian cancer have been documented by cisplatin-DNA enzyme-linked immunosorbent assay (ELISA) and atomic absorbance spectrometry (AAS). A patas monkey model was used to investigate transplacentally induced cisplatin-DNA damage in fetal tissues. During the last trimester of gestation, 5 patas monkeys were given multiple doses of cisplatin to mimic human ovarian cancer treatment. In spite of careful choice of dose and treatment conditions, cumulative toxicity occurred in monkeys given doses comparable on a mg/m2 basis to those received by the human. A total dose of 12 mg/m2 (0.625 mg/kg body weight), given in the last trimester, supported fetal viability, and multiple tissues, taken by cesarean section, were examined in the fetal monkeys. By cisplatin-DNA ELISA and AAS, maternal tissues from the monkey receiving the highest dose contained approximately twice as much DNA damage as the fetal tissues. A similar relationship was observed when we compared DNA adduct formation in fetal liver and biopsies of liver taken from the monkey dams at cesarean delivery. In all of the monkey pairs studied there were very significant levels of DNA damage in the placenta, and high adduct levels in brains of fetuses that survived treatment. Thus, cisplatin does cross the placenta in the patas monkey. These observations imply that the human fetus, for which the total maternal dose was approximately 5.4 mg platinum drug/kg body weight, may also have sustained some DNA damage.


Assuntos
Cisplatino/metabolismo , Adutos de DNA , DNA/metabolismo , Complicações Neoplásicas na Gravidez/tratamento farmacológico , Adulto , Líquido Amniótico/metabolismo , Animais , Cisplatino/sangue , Cistadenocarcinoma Seroso/tratamento farmacológico , DNA/sangue , Ensaio de Imunoadsorção Enzimática , Erythrocebus patas , Feminino , Sangue Fetal/metabolismo , Humanos , Lactente , Masculino , Neoplasias Ovarianas/tratamento farmacológico , Placenta/metabolismo , Gravidez , Espectrofotometria Atômica
17.
Arch Virol Suppl ; 9: 205-9, 1994.
Artigo em Inglês | MEDLINE | ID: mdl-8032252

RESUMO

Marmosets injected intrahepatically with nucleic acids (cDNA and RNA transcripts) representing the full-length genome of the wild-type HM-175 strain of hepatitis A virus experienced acute hepatitis and seroconversion to hepatitis A virus capsid proteins. The hepatitis was comparable in severity to that caused by infection with the wild-type virus. The viral cDNA and the hepatitis A virus recovered from the feces of an injected animal contained the same marker mutation. Therefore, intermediate cell culture steps can be omitted and the virulence of a hepatitis A virus encoded by a cDNA clone can be evaluated by direct transfection of marmosets.


Assuntos
Hepatite A/genética , RNA Viral/genética , Transfecção , Animais , Callithrix , Hepatite A/patologia , Fígado/microbiologia , RNA Viral/síntese química
18.
Carcinogenesis ; 14(9): 1805-13, 1993 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8403203

RESUMO

Since DNA adducts have been detected in the placentae of pregnant women who smoke cigarettes, the importance of these adducts as biomarkers of fetal exposure and risk has been evaluated using a non-human primate as a model. Pregnant Erythrocebus patas monkeys on days 50, 100 or 150 of gestation (term = 160 +/- 5 days) were treated once with 5-50 mg/kg benzo[a]pyrene (B[a]P), p.o. Fetuses were removed by Cesarean section 1-50 days after treatment and analyzed for DNA adducts by the nuclease P1 version of the 32P-postlabeling method. B[a]P induced high levels of DNA adducts in all fetal organs, placentae and maternal livers in all three trimesters of gestation. DNA adduct levels were higher in mid-gestation compared to early and late gestation. The major adduct detected was 10 beta-(deoxyguanosin)-N2-yl-7 beta,8 alpha,9 alpha-trihydroxy-7,8,9,10- tetrahydro-B[a]P. The adduct levels in fetal tissues increased with B[a]P dose, but at a much lower rate than in placentae or maternal livers. Preference in binding to DNA of various fetal organs was more apparent in early gestation compared to late gestation and at lower doses compared to higher doses. During early gestation and at low doses, B[a]P produced a similar level of DNA adducts in fetal lung, fetal liver, maternal liver and placenta. Individual fetal organ adduct levels correlated significantly with placental adduct levels, indicating placental and/or maternal contribution to genotoxic injuries in fetuses. However, the slopes of linear regression lines of correlation analyses varied among organs and among gestation stages at treatment, indicating fetal contribution to its own genotoxic injuries. DNA adduct levels in fetal skin were the lowest of all fetal organs tested and less affected by gestational stages at time of treatment. In contrast, DNA adduct levels in fetal liver exhibited distinct gestation stage specificity with higher adduct levels attained during mid-gestation compared to other stages of gestation. Adduct levels decreased at a much faster rate during the first 10-15 days compared to 15-50 days after B[a]P treatment. However, 10% of DNA adducts persisted 50 days after treatment in all organs studied. Together, the results suggest that placental adduction accurately indicates fetal exposure. Toxicokinetics of B[a]P and its metabolites as well as maternal, placental and fetal competence in activation and deactivation of B[a]P may be critical determinants in overall fetal risk to genetic damage. Importantly, maximal sensitivity to transplacental DNA damage may be during mid-gestation.


Assuntos
Benzo(a)pireno/metabolismo , DNA/metabolismo , Feto/metabolismo , Animais , Benzo(a)pireno/farmacocinética , Reparo do DNA , Relação Dose-Resposta a Droga , Desenvolvimento Embrionário e Fetal , Erythrocebus patas , Feminino , Idade Gestacional , Masculino , Troca Materno-Fetal , Placenta/metabolismo , Gravidez , Fatores de Tempo , Distribuição Tecidual
19.
J Nat Prod ; 56(6): 849-56, 1993 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-8350087

RESUMO

A series of artemisinin-related endoperoxides was tested for cytotoxicity to Ehrlich ascites tumor (EAT) cells using the microculture tetrazolium (MTT) assay. Artemisinin [1] had an IC50 value of 29.8 microM. Derivatives of dihydroartemisinin [2], being developed as antimalarial drugs (artemether [3], arteether [4], sodium artesunate [5], artelinic acid [6], and sodium artelinate [7]), exhibited a somewhat more potent cytotoxicity. Their IC50 values ranged from 12.2 to 19.9 microM. The presence of an exocyclic methylene fused to the lactone ring, as for artemisitene [9], led to higher cytotoxicity than 1. From the two epimeric 11-hydroxyartemisinin derivatives, the R form 12 showed a considerably higher cytotoxicity than the S form 13. Opening of the lactone ring of 1 dramatically reduced the cytotoxicity. The ether dimer 8 of 2 was the most potent cytotoxic agent, its IC50 being 1.4 microM. The variations in cytotoxicity between the structurally related compounds mostly correlated well with the theoretical capacity of radical formation and stabilization. In some cases lipophilicity or the presence of an electrophilic moiety seemed to have a determinant influence on cytotoxicity. The artemisinin-related endoperoxides showed cytotoxicity to EAT cells at higher concentrations than those needed for in vitro antimalarial activity, as reported in the literature.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Artemisininas , Carcinoma de Ehrlich/patologia , Peróxidos/farmacologia , Sesquiterpenos/farmacologia , Animais , Antineoplásicos Fitogênicos/química , Sobrevivência Celular/efeitos dos fármacos , Fenômenos Químicos , Físico-Química , Cisplatino/farmacologia , Doxorrubicina/farmacologia , Peróxidos/química , Sesquiterpenos/química , Relação Estrutura-Atividade , Sais de Tetrazólio , Células Tumorais Cultivadas
20.
J Virol ; 66(11): 6649-54, 1992 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-1328684

RESUMO

Direct inoculation of marmoset livers with an in vitro transcription mixture containing cDNA and full-length genomic RNA transcripts of hepatitis A virus resulted in acute viral hepatitis. Elevations in serum levels of liver enzymes were correlated with appearance of antibody to hepatitis A virus. Genomes of infectious hepatitis A virus isolated from the feces of transfected marmosets contained the same mutation as the cDNA template used for transfection. Liver biopsies confirmed that the virus encoded by the cDNA clone induced histopathological changes equivalent to those caused by virulent wild-type virus.


Assuntos
DNA Viral/metabolismo , Genoma Viral , Hepatite A/transmissão , Hepatovirus/genética , Transfecção , Animais , Callithrix , Clonagem Molecular , DNA Recombinante/metabolismo , DNA de Cadeia Simples , Fezes/microbiologia , Hepatovirus/patogenicidade , Injeções , Fígado/microbiologia , Fígado/patologia , Virulência
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